Physicists who want to ditch dark energy

HN Title and Framing

  • Several commenters note HN’s automatic title rewrite removed “These,” making it sound like all physicists want to ditch dark energy rather than “some,” which they see as misleading and a bit clickbaity.

Dark Energy, Dark Matter, and “Placeholders”

  • Many see dark energy and dark matter as “smudge factors” or placeholders: parameters added to make ΛCDM fit observations without knowing what they really are.
  • Others argue that in cosmology papers “dark matter” now means a specific class of cold, gravitationally interacting but electromagnetically invisible matter, not a generic fudge term.
  • There is debate over whether these count as “theories” or just hypotheses/parameterizations; some distinguish theory (full model) from hypothesis (candidate explanation).

Timescape / Inhomogeneous Cosmology

  • The timescape model is discussed as an alternative to dark energy: gravitational time dilation in large voids could make expansion appear to accelerate without a new energy component.
  • This challenges the cosmological principle (homogeneity on large scales) and the way Einstein’s equations are averaged, not the equations themselves.
  • Some find this appealing because it uses GR “properly” rather than adding mysterious components; others note it still must match diverse data sets.

Dark Matter vs Modified Gravity

  • Dark matter is seen by some as the “obvious” explanation given quantum fields and hidden sectors; others stress that simply labeling the discrepancy “matter” is already a strong theoretical choice.
  • MOND and related ideas are mentioned as having striking empirical successes (e.g., rotation curve regularities) but facing challenges like the Bullet Cluster and some dwarf galaxies.
  • There is concern that the range of acceptable dark-matter models is too narrow and overly curve-fitted to residuals.

Big Bang, Universe-as-Black-Hole, and Evidence

  • A subthread claims the Big Bang is “disproven” by early, mature galaxies and advocates a universe-as-event-horizon model; others strongly push back, calling this unevidenced and noting ΛCDM remains the mainstream framework.
  • Disagreements center on how to interpret JWST galaxy ages, the CMB, and whether alternatives are worked out or peer-reviewed.

Scientific Method, Naming, and Public Perception

  • Several comments compare dark energy/matter to luminiferous aether: historically useful but possibly destined to be discarded.
  • Others reply that past “unicorns” like the neutrino turned out to be real; current work is just the scientific method in action.
  • Some worry that naming unknowns as “dark X” suggests more certainty than exists and misleads the public, especially when popular media treat them as settled facts.